A Thermo-Electric Cooler (TEC) may be found in many applications that employ precision temperature adjustment, including optical transceivers, for example. The small size of the TEC may allow thermal adjustment of individual components, such as fiber optic laser diodes, precision voltage references, or any other temperature-sensitive device. Temperature-sensitive components may be integrated with a TEC and a temperature monitor into a single thermally-engineered module, in some situations.
Unfortunately, a TEC tends to have low efficiency or uses relatively high power, typically operating at high current.
Industry consensus has resulted in optical transceiver modules that meet common electrical, management, and mechanical specifications. Such a module is commonly referred to as a small form-factor pluggable (SFP) module. One newer high-speed variant is commonly referred to as an XFP module.
Proposal SFF-8472, Rev 10.3, released Dec. 1, 2007 (available at ftp://ftp.seagate.com/sff), for example, describes an enhanced functions monitoring interface for optical transceivers, which allows real time access to an SFP/XFP module to monitor its temperature, among other parameters. Performance or stability of optical receivers may relate, at least in part, to temperature, so monitoring or an ability to adjust temperature may be beneficial. Moreover, recent industry specifications, such as those briefly described above, may call for monitoring or adjusting temperature efficiently within the confines of a transceiver module.